Trailer tie down points for early 911

[berettafan]

Where do you guys tie the straps to your 911's for trailering?

Not inclined to use the 'hooks' under my battery boxes as they appear to be likely to tear with too much load.

Have NO idea how to secure the rear. Don't want to do the strap around the tire thing.

[tonythetarga]

depending on your wheels, you can use straps to go through the wheel and then connect your hook to the eyes of the straps on the inboard side of the wheel. Using the wheels allows the suspension to be free during transport.

[Bill Verburg]

Originally Posted by berettafan

Where do you guys tie the straps to your 911's for trailering?

Not inclined to use the 'hooks' under my battery boxes as they appear to be likely to tear with too much load.

Have NO idea how to secure the rear. Don't want to do the strap around the tire thing.

In the front you can hook to the A arms or buy something like these from Rennline, they bolt to the chassis at the front of the A arm


in back Rennline also has these




You can also go through the wheel w/ a choker, but I found that the air valve was always in the wrong spot on at least 1 wheel

[berettafan]

Bill those look great. Do you cross the straps in the rear with that type of hook?

[Bill Verburg]

Originally Posted by berettafan

Bill those look great. Do you cross the straps in the rear with that type of hook?

yes

[CurtEgerer]

Eric - why not use tire straps? Nothing touches the car.

[Grady Clay]

There are two basic ways to secure a 911 to a trailer: by the tires and wheels so the chassis ‘floats’ on the suspension and tying the chassis down so the suspension is compressed. I use both.

The major considerations are that you don’t know the direction of a load in an extreme situation. Another is no single part of the car can accept the excess load without damage. The solution is to tie the car down in many places and many directions. Redundancy is very important.

If I’m forced off the road and bounding along the median or in the borrow-pit, I want my Porsche firmly attached to the trailer. I want everything OK after, short of the trailer becoming inverted.

Best,
Grady

[Bill Verburg]

I really like the idea of tieing the wheels down, but I also like to cross the tiedowns and the spoilers on many of our cars also interfere w/ the leads from tires.

The factory ties the chassis down when shipping cars

[Walt Fricke]

If your rear rims are cookies or Fuchs or something with similarly wide spaces between the "spokes," then a short strap with D rings on each end threaded through the rim, with your ratchet strap's long end clipping both D rings together, works pretty well for most setups if you can live with not crossing the straps. On my trailer, the trailer attachment points are on the outer edges of the bed, so the straps go out a bit.

In front I use two methods, depending. My track only car with a '68 chassis has a single V hook welded to what you might call the front cross member, roughly in the middle at the latitude of the front suspension attachments. I clip my two front straps to this and run them diagonally to the trailer attachments.

With the SC I found that the hook of the typical hefty ratchet strap will fit around the diagonal rod of the front A arm. So I just clip onto that on each side.

Lots of other options - the attachment in the photo for the rear shock lower mount doesn't depend on rim configuration. You can purchase a wheel nut with a ring welded to it. Load car, remove suitable lug nut, screw this one on, and attach. Guys who like the over the wheel stuff. I trailer my track only car with "trailer rims": old steel rims with old (and quite tall) tires. I just hook into the slots on these tough old rims with the strap's hook - really quick and easy. On it goes.

One thing I find especially helpful is the kit Racer Wholesale sold (still does, I hope) which allows you to attach the spring hook part directly to the ratchet, eliminating the length of sewn webbing. Helps get the ratchet out of the way of the car by moving it as close to the trailer attachment as possible.

If you attach with a strap through a wheel, be sure to check after driving for a while. Sometimes the pull isn't normal to the wheel due to where the spokes happen to be, but the wheel will eventually slide so the load is lined up. This will put slack in the strap.

As with many things, how far you go depends in part on how you approach things. A buddy would drive his car onto the trailer, pull on the hand brake, and drive on home. No problems. Of course, if he ran off the road or imposed other unexpected loads, - - - -

And you can't cover all the bases. A buddy had a semi run into the rear of his two car trailer. Destroyed both cars, or nearly so. Damn near did him in also. Strap strength didn't matter there.

Walt Fricke

[berettafan]

The through the wheel straps seem like they'd cause alignment and/or bearing issues.

Curt I'm just not comfortable w the idea of not crossing the straps. Also worried about overtightening and doing damage somehow. How often do you trailer your car? How tight do you make the straps?

[CurtEgerer]

I trailer frequently. I'm 100% comfortable with the set-up I use. Not visible in the photo due to the trailer fender is how the other side of the tire straps connect. They go almost straight down and then thru a D-ring mounted to the bed so the tire straps hold each tire down vertically and individually to the trailer. They are ratcheted down very firmly, creating a high degree of friction between the tire and trailer bed. The tires can't hop or slide, at all. As such, I don't see the need to cross the straps with this method (other methods? YES). If I get into some sort of sideways slide with enough force to break these tires free from the straps, I'm probably going to be calling Hagerty anyway

As a minor note, a 911 should be backed onto the trailer so the majority of weight is on the tongue. I've tried both ways and honestly feel very little difference in handling, but my trailer is a heavy steel unit too. This might be more important with an aluminum trailer and/or a lighter tow vehicle.

[Bill Verburg]

Originally Posted by CurtEgerer

.....
As a minor note, a 911 should be backed onto the trailer so the majority of weight is on the tongue. I've tried both ways and honestly feel very little difference in handling, but my trailer is a heavy steel unit too. This might be more important with an aluminum trailer and/or a lighter tow vehicle.

Whether to go on forward or backward is more a function of the trailer design. On my Trailex the axles can be mounted over a range fore/aft. Specify the vehicle when purchasing the trailer and they will correctly place the axles and the wheel stops for that vehicle so that it can be put on forward.

[175K911]

I'm a firm believer in using wheel nets. They locate the car fore and aft and side to side, still let the car float on it's suspension. And they allow for easily tieing down lowered casrs too if you also run an idler on the E-track which is what I use.

I've also used wheel straps in the rear with my front nets. Lots of people say it hurts the alignment, but in several years of towing all over the northeast US to track events, I've never had an issue. Frankly the side loads of 100+ mph turns places greater forces on the alignment than static forces on a trailer.

And as Bill said, how you load the car on the trailer is very much a function of trailer design. I can load my car on my trailer, have my car positioned with the tail hanging a few inches off the back and still have 700-800lbs of tongue weight when I have 8 wheels and tires on the tire rack and the tongue box is full of tools, spares, etc.

In the pic here you can barely see my blue nets, custom made for the width and OD of my tires. I welded E-tracks to the trailer under the front tires, the rear strap of the net clips to the track securely. The net has 4 straps over the top of the tire with webbing both front and rear and really locks the tire down. The front of the strap goes straight down to an idler pulley clipped to the track so the strap can make a clean 90 degree turn and goes forward low enough to clear my front spoiler. I route the strap into the ratchet clipped to the d-rings about 2 feet ahead of the spoiler. Once tightened down, there's no way the car is going anywhere. My winter project is to weld E-track under the rear tires and get two more nets for the back. Then I could completely loose a corner and the car still wouldn't go anywhere. (BTW- the rear straps in the pic are hooked to the Rennline brackets that attach to the lower shock bolts but I don't tow that way anymore. The hooks on the straps started wearing the Rennline parts away. On a 900 mile trip to VIR, one of the rear hooks wore the Rennline part a good 1/4" and caused the strap to keep getting loose. So I went back to my wheel straps for the trip home.)

[berettafan]

Aha! So the tire straps attach directly to the trailer right at the tire and not at the front and rear? Or is it both?

Curt/Ed do you guys have any pics of this? I REALLY like the idea of not putting anything but downward pressure on the wheels.

[175K911]

Unfortunately I don't have a good pic of my 911 tied down with the wheel nets but these are a few pics from Mac's website where I got the equipment.

This shows how the strap in configured, though in my case I had Colin at Mac's make custom straps for me, sized to fit my 235/40-17 on 8" rim. I needed good support but didn't want to come down as far as in this pic because I needed clearance in the back for the 996TT calipers and hard lines:



And rather than put D-rings all over the floor of the trailer, I welded on a 5' length of E-track so I could move the car forward and back to get the best tongue weight, depending on how much weight I had in the storage box and how many wheels and tires were on the tire rack:



And this is the idler I use for the non-fixed strap to make the 90 degree bend to the ratchet:



Like all things Porsche, there are a number of different ways to tie a car down. But this is what I've decided on after more than 20 years and probably 50K miles of pulling open and enclosed car trailers. Of course I check all straps at every fuel stop too, jsut to be safe.

[Grady Clay]

Check this thread:

Best method for securing 911 to trailer?

Best,
Grady

[ZOA NOM]

I don't recommend the Torsion Bar end tie downs... I only use over-the-tire straps up front, and the Rennline eyes on the rear shock mounts.

The damage shown was the result of a fender-bender rear ender that ruined my track weekend.

[Grady Clay]

Ed,

Where did this part come from?



I use similar pieces.
The Kinedyne FE8029-1 puts the strap angle closer to the track.




The load is at 45° to the track but closer puts less bending forces on the fitting.
Note that the load on the fitting is 1.4 X the tension load in the strap.
E-track load ratings are at perpendicular.

Best,
Grady

[175K911]

Originally Posted by Grady Clay

Ed,

Where did this part come from?



I use similar pieces.
The Kinedyne FE8029-1 puts the strap angle closer to the track.




The load is at 45° to the track but closer puts less bending forces on the fitting.
Note that the load on the fitting is 1.4 X the tension load in the strap.
E-track load ratings are at perpendicular.

Best,
Grady

All my straps and hardware came from Mac's Custom Tiedowns. Great people to deal with and they'll do whatever they can to accomodate custom applications. They make a lot of one-off straps and tie downs for show cars.

http://www.macscustomtiedowns.com/

I also have some custom e-track pieces he made up for me that have two e-track clips per pivot and use tie down webbing with a floating d-ring to run the strap through. I can clip it in with the clips 2 or 3 slots apart to get the pivot ring as low as possible but it can still float a bit until snugged down so the strap finds the best position to prevent chafing. And it spreads the load over two slots per wheel to avoid the 45 degree force on the track, as you referenced.

[Buckterrier]

Great thread. I just purchased a trailer and have no idea how to tie down the Carrera
But I do now, (or at least will ask less stupid questions)